[R] How to draw an observation uniformly from a given dataset?

[David Forrest]

On Wed, 8 Sep 2004 wanr at ucalgary.ca wrote:

> Hi all,
>
> I have two questions stated below:
>
> 1. How to draw an observation uniformly from a given data?
>
> For example, I have a dataset (or dataframe) with 10 observations (with a
> set of variables) and I want to "uniformly" select an observation from this
> given dataset, that is, the probability of selecting each observation is
> 1/10.

sample(1:10,3,replace=TRUE)

>
> 2. How to do this "combinations"?
>
> source vector = (1,2)
> the length of the target vector = 3
>
> My expected outputs should be:
> 111, 112, 121, 122, 211, 212, 221, 222.

sample(c(1,2),3,replace=TRUE)

Dave
-- 
 Dave Forrest
 drf at vims.edu                                    (804)684-7900w
 drf5n at maplepark.com                             (804)642-0662h
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